Method for fabricating semiconductor device

Abstract

The accuracy in forming a gate electrode or an interconnect is improved by using a dummy gate electrode or a dummy interconnect. In addition, the dummy gate electrode or the dummy interconnect is removed, so that a region where the dummy gate electrode or the dummy interconnect has been disposed can be used as a region for forming another composing element.

What is claimed is:  
     
       1. A method for fabricating a semiconductor device comprising the steps of: 
       simultaneously forming a gate electrode and a dummy gate electrode on a semiconductor substrate;  
       removing said dummy gate electrode;  
       forming an interlayer insulating film on said semiconductor substrate after removing said dummy gate electrode; and  
       forming, in said interlayer insulating film, a plug in a region overlapping with at least a part of a region where said dummy gate electrode has been disposed.  
     
     
       2. The method for fabricating a semiconductor device of  claim 1 , 
       wherein a photomask used for forming said dummy gate electrode is used in removing said dummy gate electrode.  
     
     
       3. A method for fabricating a semiconductor device comprising the steps of: 
       forming a pair of impurity diffusion layers serving as source and drain regions in surface portions of a semiconductor substrate;  
       simultaneously forming a gate electrode on said semiconductor substrate between said pair of impurity diffusion layers and a dummy gate electrode on at least one of said pair of impurity diffusion layers; and  
       removing said dummy gate electrode.  
     
     
       4. The method for fabricating a semiconductor device of  claim 3 , 
       wherein a photomask used for forming said dummy gate electrode is used in removing said dummy gate electrode.  
     
     
       5. The method for fabricating a semiconductor device of  claim 3 , further comprising, after the step of removing said dummy gate electrode, the steps of: 
       forming an interlayer insulating film on said semiconductor substrate; and  
       forming, in said interlayer insulating film, a plug in a region overlapping with at least a part of a region where said dummy gate electrode has been disposed.  
     
     
       6. A method for fabricating a semiconductor device comprising the steps of: 
       simultaneously forming an interconnect and a dummy interconnect on a semiconductor substrate;  
       removing said dummy interconnect;  
       forming an interlayer insulating film on said semiconductor substrate after removing said dummy interconnect; and  
       forming, in said interlayer insulating film, a plug in a region overlapping with at least a part of a region where said dummy interconnect has been disposed.  
     
     
       7. The method for fabricating a semiconductor device of  claim 6 , 
       wherein a photomask used for forming said dummy interconnect is used in removing said dummy interconnect.  
     
     
       8. A method for fabricating a semiconductor device comprising the steps of: 
       forming, on a semiconductor substrate, an interlayer insulating film provided with a plug;  
       simultaneously forming an interconnect on said interlayer insulating film and a dummy interconnect on said plug; and  
       removing said dummy interconnect.  
     
     
       9. The method for fabricating a semiconductor device of  claim 8 , 
       wherein a photomask used for forming said dummy interconnect is used in removing said dummy interconnect.  
     
     
       10. The method for fabricating a semiconductor device of  claim 8 , further comprising, after the step of removing said dummy interconnect, the steps of: 
       forming a second interlayer insulating film on said interlayer insulating film; and  
       forming, in said second interlayer insulating film, a second plug in a region overlapping with at least a part of a region where said dummy interconnect has been disposed.  
     
     
       11. A method for fabricating a semiconductor device comprising the steps of: 
       simultaneously forming a virtual gate electrode and a dummy gate electrode on a semiconductor substrate;  
       forming a first resist film on said semiconductor substrate in a region where none of said virtual gate electrode and said dummy gate electrode is formed;  
       removing said virtual gate electrode and said dummy gate electrode;  
       forming a second resist film in a recess from which said dummy gate electrode has been removed; and  
       forming a gate electrode in a recess from which said virtual gate electrode has been removed.  
     
     
       12. The method for fabricating a semiconductor device of  claim 11 , 
       wherein a photomask used for forming said dummy gate electrode is used in forming said second resist film.  
     
     
       13. A method for fabricating a semiconductor device comprising the steps of: 
       simultaneously forming a virtual interconnect and a dummy interconnect on a semiconductor substrate;  
       forming a first resist film on said semiconductor substrate in a region where none of said virtual interconnect and said dummy interconnect is formed;  
       removing said virtual interconnect and said dummy interconnect;  
       forming a second resist film in a recess from which said dummy interconnect has been removed; and  
       forming an interconnect in a recess from which said virtual interconnect has been removed.  
     
     
       14. The method for fabricating a semiconductor device of  claim 13 , 
       wherein a photomask used for forming said dummy interconnect is used in forming said second resist film.